A photolithography process for forming patterns may be required to manufacture semiconductor devices.
In a photolithography process, a resist layer may be coated on a target layer to be patterned. An exposure and development process may be performed, thereby forming a patterned resist layer. An etching process may be performed, for example by using the resist layer pattern as a mask. A target layer may thus be patterned.
In a related art photolithography method an adhesive agent or BARC (Bottom Anti Reflective Coating) may be deposited on a wafer, and may increase adhesion between a photoresist layer and a lower layer.
A heating process may then be performed. Edge Bead Remover (EBR) may next be performed while coating the photoresist layer. Beads may refer to photoresist residues remaining at an edge of a wafer.
Wafer Edge Exposure (WEE) may be performed to remove beads at an edge of the wafer.
An exposure and development process may be performed with respect to the coated photoresist layer by using a mask. This may develop a pattern transferred by using a mask and beads exposed at the edge of the wafer through WEE. A photoresist layer pattern transferred with a mask pattern can be obtained through such a series of procedures.
However, according to the related art, the EBR may be performed together with a photoresist layer coating process, and may use a thinner. Since the thinner drops on an inner surface of a wafer in this procedure, the thinner may melt an otherwise normally formed photoresist layer, which may result in pattern failure.
Further, according to the related art, only one unit is generally used for track equipment due to the size of the unit in a separately performed WEE process. Therefore, the entire process speed is delayed and a product yield may be lowered.